Acceptance Sampling Plans for Percentiles Based on the Exponentiated Half Logistic Distribution

In this article, acceptance sampling plans are developed for the exponentiated half logistic distribution percentiles when the life test is truncated at a pre-specified time. The minimum sample size necessary to ensure the specified life percentile is obtained under a given customer’s risk. The operating characteristic values (and curves) of the sampling plans as well as the producer’s risk are presented. Two examples with real data sets are also given as illustration

Disentangling the dominant drivers of gravity wave variability in the Martian thermosphere

In this study, we extracted the amplitudes of the gravity waves (GWs)from the neutral densities measured in situ by the neutral gas and ion mass spectrometer aboard the Mars atmosphere and volatile evolution mission. The spatial and temporal variabilities of the GWs show that solar activity (the F10.7 cm solar flux corrected for a heliocentric distance of 1.66 AU), solar insolation, and the lower atmospheric dust are the dominant drivers of the GW variability in the thermosphere. We developed a methodology in which a linear regression analysis has been used to disentangle the complex variabilities of the GWs. The three dominant drivers could account for most of the variability in the GW amplitudes. Variability caused by the sources of GWs and the effects of winds and the global circulation in the mesosphere and lower thermosphere are the other factors that could not be addressed. The results of the present study show that for every 100 sfu increase in the solar activity, the GW amplitudes in the thermosphere decrease by ~9%. Solar insolation drives the diurnal, seasonal and latitudinal variations of ~9%, ~4% and ~6%, respectively. Using the historical data of the dust opacity and solar activity, we estimated the GW amplitudes of the Martian thermosphere from MY 24 to MY 35. The GW amplitudes were significantly reduced during the maximum of solar cycle 23 and were highest in the solar minimum. The global dust storms of MY 25, 28, and 34 lead to significant enhancements in the GW amplitudes.Comment: Accepted for publication in the astrophysical journal; 18 page

Vibration Characteristics of Aircraft Engine-Bladed-Disk Assembly

This paper is concerned with the vibration characteristics of a gas-turbine blade-disk assembly and a third stage of compressor blade-disk assembly of an orpheus aircraft engine. The assembly is analyzed by considering each component individually and then combining them together with a receptance coupling technique by matching forces and displacements at each junction point. The blade is modelled by number of free-free aerofoil section beams staggered at different angles to the plane of the disk, and the non-uniform disk is modelled as numbers of concentric annuli. The natural frequencies and mode shapes for each case have been obtained. Results obtained are verified by testing both the above assemblies on a microprocessor based vibration exciter and real time analyzer. The mode shape corresponding to each natural frequency was obtained by probing with hand held accelerometer

Grid Connected Distributed Generation System with High Voltage Gain Cascaded DC-DC Converter Fed Asymmetric Multilevel Inverter Topology

The paper presents distributed generation (DG) system in grid connected mode of operation with asymmetric multi-level inverter (AMLI) topology. Cascaded type DC-DC converter is employed to feed proposed AMLI topology. The DG output voltage (generally low voltage) is stepped up to the required level of voltage using high-gain DC-DC converter. Proposed AMLI topology consists of capacitors at the primary side. The output of high-gain DC-DC converter is fed to split voltage balance single-input multi-output (SIMO) circuit to maintain voltage balance across capacitors of AMLI topology. Cascaded DC-DC converters (both high-gain converter and SIMO circuit) are operated in closed-loop mode. The proposed AMLI feeds active power to grid converting DC type of power generated from DG to AC type to feed the grid. PWM pattern to trigger power switches of AMLI is also presented. The inverting circuit of MLI topology is controlled using simplified Id-Iq control strategy in this paper. With the proposed control theory, the active power fed to grid from DG is controlled and power factor is maintained at unity. The proposed system of DG integration to grid through cascaded DC-DC converters and AMLI structure is validated from fixed active power to grid from DG condition. The proposed system is developed and results are obtained using MATLAB/SIMULINK software

A GRID CONNECTED PHASE MONITORING SYSTEM GOVERNING STABLE CURRENT

Various power transfer technology is requested ac/electricity transformation to acquire a constant frequency ac power. Once the wind speed varies, the servo motor supplies a compensatory energy to keep constant generator speed. Within this paper, an optimum power tracking control plan is suggested. The suggested MPTC plan includes two control loops. The extra servo motor power can also be changed into electricity, and output in to the load. This paper presents a singular converter less wind turbine having a control framework that includes an excitation synchronous generator, magnet (PM) synchronous servo motor, signal sensors, and servo control system. The control system design concepts maintain power flow balance between your input and also the output and, concurrently, pressure the generator frequency to synchronize using the utility grid. Because of the problem in precisely estimating the wind speed, the suggested MPTC plan measures the motor output power because the reference signals to look for the generator output power. For any typical three phases, four rods excitation synchronous generator, the generator output power is controlled by the excitation controller, with the slip rings, using the appropriate excitation current delivered to the armature winding. The traditional motor current feedback controller can avoid immediate current stress towards the servo driver. The direct drive magnet synchronous wind turbine uses variable speed and power ripper tools technologies to satisfy the grid connection needs that have benefits of being gearless. Fraxel treatments continue to be put on the servo motor control to enhance the control performance. Experimental results show the suggested wind turbine system achieves high end power generation with salient power quality

Instagram Influencers Credibility Dimensions and Purchase Intention of Followers: Empirical Evidence

The advent of SMIs has primarily altered the means business connect with their prospects and customers. Currently, many SNSs enables SMIs to endorse the products, share opinions, provide feedback, and communicate with their followers either publicly or privately. This research aims to determine the mediating effect of loyalty of followers towards the influencer and ascribed opinion leadership on SMIs dimensions (expertise, trustworthiness, and attractiveness) and purchase intention relationship from the perspective of Instagram users in India. To measure the objective, the study acquired responses from 250 Indian Instagram users in the age group of 18-24. Results indicated that the purchase intention of followers is positively influenced by expertise, trustworthiness, ascribed opinion leadership, and loyalty of followers towards the influencer dimensions. Here, ascribed opinion leadership and loyalty of followers towards the influencer acts as an effective arbitrator between SMIs dimensions (expertise, trustworthiness, and attractiveness) and purchase intention relationship. The study suggests that before engaging SMI to promote the brand, the companies should understand the perception of followers towards the influencer in terms of expertise, attractiveness, and trustworthiness dimensions

Advanced Integrated Fire Halt Robot

This paper develop a fire halt robot using RF technology to control the fire accidents. This robot is designed with water tanker, a pump, elide fire ball and carbon dioxide cylinder which are controlled by wireless communication. An 8051 series of AT89S52 microcontroller is used to design this robot. In this model Transmitter pass the commands to the Receiver using buttons to control the movement of the robot as per the required application. By using three motors at receiver side and are interfaced to the microcontroller for the movement of the robot and to position the arm of the robot. A motor driver IC is interfaced to control the fire extinguishing devices